1. Field of the Invention
The present invention relates generally to space heaters, and more particularly, to an improved gas-fired radiant space heater for use in broiler houses or turkey barns which includes a burner that permits safe, efficient operation in dusty environments and at low gas pressures.
2. Description of the Prior Art
In grow-out barns for turkeys or broilers, a heating means is often required to maintain a temperature conducive to development of these birds. The heating means must provide sufficient heat for these large barns while operating safely and reliably in the very dusty environment that is present. Several types of space heaters for this purpose are presently available.
One type is a space heater which requires a fan unit to ensure proper combustion. The requirement for a fan unit not only increases the cost of these heaters but also increases the necessary maintenance and concomitantly reduces the reliability and efficiency. Specifically, the fan unit collects dust which reduces the air flux blown by the fan. Reduced air fluence both decreases the circulation of heated air and the combustion efficiency, resulting in reduced heating and potentially hazardous conditions due to partial combustion.
Gas-fired space heaters, which do not require a fan for proper combustion, have also been employed for heating grow-out barns. In order to avoid the need for a fan unit which provides sufficient air circulation for proper combustion, these heaters operate at a lower combustion rate and thus, have a lower heating capacity. As a result, a large number of these low heating capacity (e.g., about 28,000-30,000 B.T.U.) units are required which increases the cost to the grower.
To overcome these problems with low-pressure, gas-fired space heaters, high pressure, gas-fired heaters which use a target-type burner have also been developed. The high input pressure (e.g., 10-20 p.s.i.) ensures proper combustion without the need for a fan while also providing higher heating capacities. High-pressures in a poultry-house environment may be dangerous, and fires have resulted from improper use of this type of heater. Instructions for these heaters indicate that when insufficient heat is produced the grower should increase the gas pressure to increase the gas flow rate and thereby increase heat generation. Further increasing the pressure, however, further increases the safety hazards.
Bunsen-type gas burners which operate at normal pressures have been used in for boilers, furnaces, and other related heating equipment. Typically, these burners have a horizontal venturi with an elbow transition into a vertical single-port burner. This design has also been used in a low heating capacity (e.g., 30,000 B.T.U.) brooder-type device; however, this device was recalled and removed from manufacture because of chronic obstruction by dust in the horizontal venturi and elbow transition.
There are also general purpose space heaters available which do not require fan units, operate at normal pressures, and have sufficient heating capacity. These heaters, however, are not well suited for dusty environments because they typically employ a multi-port Bunsen-type gas burner which is prone to obstruction. Again, burner obstruction leads to incomplete combustion which may result in reduced heating and dangerous operating conditions.
3. Objections of the Invention
Accordingly, an object of the present invention is to provide a gas-fired radiant space heater which will efficiently and safely operate in dusty environments such as that found in turkey barns and broiler houses, and at normal low gas pressures.
A related object of the present invention is to provide a burner which may be safely operated under the described conditions.
Another related object of the present invention is to provide a heater structural design which permits adjustment of the air entrainment into the burner and into the combustion region.
A further related object is to provide an economical, simple structure for sealing the control components from the dusty environment while allowing easy access for maintenance.
Yet another object of the present invention is to provide a heater structural design which avoids controller failure due to excessive temperature caused by the heat generation.
These and other desirable objects are accomplished by the present invention in an economical structure which may be safely operated with little or no personal attention. In the particular embodiment set forth below, a radiant space heater for use by poultry or livestock growers incorporates these objects and advantages and thus, represents an improvement over prior art spacer heaters.
Objects and advantages of the present invention are set forth in part herein and in part will be obvious herefrom, or may be learned by practicing the invention, the same being realized and attained by means of the instrument and combinations pointed out in the appended claims.
The invention consists in the novel parts, constructions, arrangements, combinations, steps and improvements herein shown and described.